非对称加密算法RSA

package com.imooc.security.rsa; import java.security.KeyFactory; import java.security.KeyPair; import java.security.KeyPairGenerator; import java.security.PrivateKey; import java.security.PublicKey; import java.security.interfaces.RSAPrivateKey; import java.security.interfaces.RSAPublicKey; import java.security.spec.PKCS8EncodedKeySpec; import java.security.spec.X509EncodedKeySpec; import javax.crypto.Cipher; import org.apache.commons.codec.binary.Base64; /** * 非对称加密算法 * @author Bingo_Ge * RSA算法（事实上的标准，也可以用在数字签名） */ public class ImoocRSA { private static String src = "imooc security rsa"; public static void main(String[] args) { jdkRSA(); } public static void jdkRSA() { try { //1.初始化密钥 KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA"); //使用RSA非对称加密方式 keyPairGenerator.initialize(512); KeyPair keyPair = keyPairGenerator.generateKeyPair(); //生成密钥对 RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic(); RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate(); System.out.println("RSAPublicKey:" + Base64.encodeBase64String(rsaPublicKey.getEncoded())); System.out.println("RSAPrivateKey:" + Base64.encodeBase64String(rsaPrivateKey.getEncoded())); //2.私钥加密，公钥解密（加密） PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded()); KeyFactory keyFactory = KeyFactory.getInstance("RSA"); PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec); Cipher cipher = Cipher.getInstance("RSA"); cipher.init(Cipher.ENCRYPT_MODE, privateKey); byte[] result = cipher.doFinal(src.getBytes()); System.out.println("私钥加密，公钥解密（加密）:" + Base64.encodeBase64String(result)); //3.私钥加密，公钥解密（解密） X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(rsaPublicKey.getEncoded()); keyFactory = KeyFactory.getInstance("RSA"); PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec); cipher.init(Cipher.DECRYPT_MODE, publicKey); result = cipher.doFinal(result); System.out.println("私钥加密，公钥解密（解密）:" + new String(result)); //4.公钥加密，私钥解密（加密） x509EncodedKeySpec = new X509EncodedKeySpec(rsaPublicKey.getEncoded()); keyFactory = KeyFactory.getInstance("RSA"); publicKey = keyFactory.generatePublic(x509EncodedKeySpec); cipher.init(Cipher.ENCRYPT_MODE, publicKey); result = cipher.doFinal(src.getBytes()); System.out.println("公钥加密，私钥解密（加密）:" + Base64.encodeBase64String(result)); //5.公钥加密，私钥解密（解密） pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded()); keyFactory = KeyFactory.getInstance("RSA"); privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec); cipher = Cipher.getInstance("RSA"); cipher.init(Cipher.DECRYPT_MODE, privateKey); result = cipher.doFinal(result); System.out.println("公钥加密，私钥解密（解密）:" + new String(result)); } catch (Exception e) { e.printStackTrace(); } } }